Substituted 4,5,6,7-tetrahydroindoles and their fused derivatives. Synthesis and cytotoxic activity towards tumor and normal human cell lines

Abstract

This work has been carried out to explore the reaction of 2-cyanoacetohydrazide with cyclohexanone to form 4,5,6,7-tetrahydroindole derivatives. 2-Hydroxy-4,5,6,7-tetrahydro-1H-indole-3-carbonitrile was used as the starting material for a series of novel heterocyclic products containing fused oxazine, pyran, pyrazole, pyridazine, and thiophene rings. The antitumor activity evaluation of the newly synthesized compounds against three human tumor cells lines, breast adenocarcinoma (MCF-7), non-small cell lung cancer (NCI-H460), and CNS cancer (SF-268), and with normal fibroblast cells (WI 38) showed that some of these compounds exhibit much higher inhibitory effects towards the three tumor cell lines than the reference drug doxorubicin while being minimally active towards normal cells.